The Norwegian Mother and Child Cohort Study (MoBa) is an ongoing pregnancy cohort study, with the aim of enrolling 100,000 pregnancies by 2008. The study is based on questionnaires completed by the mother and father, and biological specimens are collected from the mother, father and child. The main purpose of the study is to find causes of diseases. NIEHS is providing partial support for the study, and in 2002 expanded the data collection protocol to include collection of more biologic specimens from the mothers during the 17th week of pregnancy (additional serum, a specimen of whole blood collected in a trace-element free container, and urine). These specimens will enhance the ability to examine the relation of environmental exposures in relation to various health outcomes in the children and their mothers. As of June 30, 2007, 62,118 subjects had provided blood and urine that was collected in conjunction with NIEHS. We expect at least 10,000 additional subjects to be recruited before enrollment closes.[unreadable] Because the study is still in the subject enrollment phase, writing of scientific reports is still relatively limited. At NIEHS, we are developing studies that will be nested within MoBa. The current list of planned studies includes: Changes in Exposures Across Pregnancies, Pregnancy Serum Levels of Perfluoroalkyl Chemicals in Relation to Infant Growth, Risk Factors for Cleft Lip and Palate, A Search for the Non-mendelian Transmission of Human Genes, Mother's Physical Activity During Pregnancy and Fetal Loss, Dietary Intake and Gestational Diabetes, Physical Activity in Pregnancy and Infant Neurodevelopment, Maternal Autoantibodies against Folate Receptors as a Risk Factor for Folate Sensitive Birth Defects, Organophosphate Pesticide Exposure and Risk of Autism, and the Etiology of Cerebral Palsy.